


nemusíš se doslova klanět

by armethaumaturgy



Series: Left Hand AU [4]
Category: Undertale (Video Game)
Genre: Cross (X-tale) - Freeform, Cross (X-tale)/Dust (Dusttale), Cross is here to try and make this castle Work, Dust (Dusttale) - Freeform, Ecto-Genitalia (Undertale), Exhaustion, Explicit Sexual Content, Gentle Sex, Hand Jobs, Illustrations, Implied/Referenced Rape/Non-con, M/M, Nightmare (Dreamtale) - Freeform, Panic Attacks, Praise Kink, Unhealthy Coping Mechanisms, crossdust
Language: English
Status: Completed
Published: 2021-02-26
Updated: 2021-02-26
Packaged: 2021-03-16 17:33:21
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,215
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29704098
Author URL: https://archiveofourown.org/users/armethaumaturgy/pseuds/armethaumaturgy
Summary: “He’s more useful alive, isn’t he?”“I can’t believe you think I’d let him die,” Nightmare shot back, flatly. His pen glided over the paper with a soft noise, monotone and irritating.Cross had to take a couple deep breaths, if only to calm himself down. “I’m not sayingyou,boss. I’m saying one day he’ll take it too far and all that’s gonna be left of him is a fucking pile of his namesake.”
Relationships: Sans/Sans (Undertale)
Series: Left Hand AU [4]
Series URL: https://archiveofourown.org/series/2181261
Comments: 19
Kudos: 132





	nemusíš se doslova klanět

**Author's Note:**

> takes place immediately after [buď vždy na mojí straně](https://archiveofourown.org/works/29683377), even if the lyrics are backwards haha.  
> title from ewa farna's 'na ostří nože' yet again.  
> and the *chefs kiss* art is by my dear fiancee, @Reclawedcat on twitter 💜💜💜

Nightmare seemed about as nonplussed as Cross felt furious.

He’d known this conversation wouldn’t go smoothly, but to actually see Nightmare blatantly ignoring the problem? Cross’ instincts were screaming; that wasn’t what a good leader did, that was no way to care for your subordinates. He didn’t say any of that, because no matter what Nightmare did, he was above Cross, and his respect wasn’t broken that easily.

“He’s not a child,” Nightmare said, shrugging. He’d barely looked up from the new treaty for Fellswap #71, but there was no doubt he could feel Cross’ emotions, as all over the place as they were. “I can’t stop him from doing whatever he wants outside a mission.”

Cross wanted to have hair, just so he could tear it out. He wanted to drive his weapon into the table, just so Nightmare would pay attention. He wanted to yell at him, because he _could!_ That was the whole point; he was their fucking leader, he could tell them to do whatever he wanted!

But Cross did none of those things. He was a trained guard, and it was unbefitting of him to lose his cool.

“You can, boss,” he said, as calmly as he could make his voice. “He’s more useful alive, isn’t he?”

“I can’t believe you think I’d let him die,” the dark skeleton shot back, flatly. His pen glided over the paper with a soft noise, monotone and irritating.

Cross had to take a couple deep breaths, if only to calm himself down. “I’m not saying _you,_ boss. I’m saying one day he’ll take it too far and all that’s gonna be left of him is a fucking pile of his namesake.”

Finally, Nightmare looked up, setting his pen down. His stare was hard, and he cocked his visible browbone. “Again, Cross. _What_ makes you think I’d let him die?”

“At this rate, it won’t be in your jurisdiction.”

“Everything in this castle is under my jurisdiction. Why don’t you ask him if he knows what he’s doing?”

Cross should’ve been surprised that they had an audience, but frankly, he wasn’t. He turned his head to watch Dust come into the office as the door opened. He seemed calmer, and Cross forced down the slew of ideas as to how exactly he got to that point.

“You called?” Dust asked, an easy grin on his face, always with an edge to it.

“Dust, how are you managing your LV?”

Dust barked out a laugh, shoulders shaking as he shoved his hands into his pockets and looked at Cross. There was something in his eyelights, but he couldn’t place it, not right away. “Peachy, like always.”

Cross sent him a Look. With a capital L. “Your neck’s leyline is broken. I heard you crying two wings down.”

Dust just shrugged again and turned his smirk at Nightmare. “A good meal, wasn’t it?” he asked, looking like he already knew the answer.

Nightmare graced them both with a rare chuckle. “Indeed.”

Dust’s smirk upturned, wider now. He almost looked… proud? Cross found himself stunned to silence as he watched him readjusting his scarf and mumble something incomprehensible into it. He knew Nightmare fed off of negative emotion — hell, Cross himself was probably a fancy snack to him right now — but for Dust to be purposefully making himself miserable to feed him when there was an entire multiverse for that? It didn’t make sense to him.

“Dust,” he spoke, silently proud of the fact that his voice didn’t waver. He was sure he’d already overstepped half a dozen lines with Nightmare. He didn’t know how much leeway his status as the group’s second in command allowed him, but what was one more transgression when he already had so many? His mind flashed with unending white as far as the eye could see, but he forced the image down, into the back of his mind where it belonged. “Meet me at the training grounds.”

Dust inclined his head, and then he grinned again. “What? Gonna show me how good you are with _your_ knives? I can call Killer, too, make it a learning party.”

Cross forced his hands to be still.

“Alone, Dust. Boss, permission to leave?”

Nightmare regarded him with amusement, a soft scoff leaving him. “Go ahead.”

Given leave, Cross marched his way out of the office and down the hallways. The walk gave him time to calm down. He found himself appalled at himself. Were Undyne here, she would’ve already put him back in his place for losing his temper and for stepping out of the line. Worse yet, he could imagine Gaster doing the same, giving him that disappointed look, like Cross had done something so deep beneath his expectations he wasn’t worth even a word. He shook his head to clear it. Neither of them were here, and he was the captain now.

And he’d live up to his duties.

As expected, Dust was already there when he arrived at the grounds. It was just a piece of the forest that encircled the castle, flattened to provide no cover for clean battles. Before Dust had a chance to say a thing, Cross’ arms crossed over his chest.

“Give me ten blasters.”

Dust’s smirk fell in favor of a frown, his confusion palpable. Cross tapped his foot.

“Don’t make me wait, Dust.”

Obeying, ten blasters came into being behind Dust, crackling with charged magic as they twitched in the hover, not unlike their master.

“Good. Five on each side, facing each other.” The blasters split, midway between them even as they faced each other. Cross hadn’t missed the way Dust stood a bit straighter at the praise, though. It made sense, given the circumstances, and it would make this so much easier. Cross schooled his expression into something neutral, and tried to keep it that way. “Fire.”

On command, all the blasters fired, their beams meeting at the halfway point. The shockwave from the blasts rattled the ground and created a gust of air that made Cross’ clothes flutter around wildly. He ignored it.

“Hold the blasts,” he ordered, catching a glimpse of Dust’s face behind the purple magic. His eyelight blazed with the same glow.

Cross found himself musing on the other’s SOUL traits. He knew what determination felt like, very intimately, but it was interesting that rather than Dust’s patience, it replaced his innate justice. Personally, Cross thought it was the other way around, because he’d never seen the other skeleton show an ounce of patience.

Even now it waned, his face set into a glare, aimed at one of the blasters. Or maybe behind it, it was hard to say. All the blasters were equal power, and their fight would only end once they ran out of steam. And with them, Dust.

“Give them more power,” Cross told him, and the shift was all but visible; he had to dig his heels into the ground to keep himself steady against the pushback.

Small beads of sweat were forming on Dust’s skull, shining in the glow of the magic. This was probably the clearest he’d ever seen Dust’s face, and the fact that it was through a layer of purple spoke volumes. The dark circles under his sockets were so prominent Cross wondered if he’d even slept the past few days.

But he couldn’t help being amazed. His mental count had reached four minutes, and the blasters had yet to falter. He’d never tried to hold one, but he knew he couldn’t manage even half of this time, much less with ten of them at once.

Four and a half.

“Keep it up,” Cross said, his voice barely audible over the screeching of magic. Everyone inside could probably hear them, but Cross had a feeling that if anyone did come, it would be to watch, not interrupt.

Five minutes.

Six minutes.

Dust readjusted his stance, the sweat rolling down his cheekbones.

Six and a half.

Seven minutes.

The blasters dipped in their hover, the glow of the blasts dimming. Cross shook his head. “Keep going. More juice.”

Dust’s teeth turned up at the corner, his grimace boring into nothing in particular.

Eight minutes.

Nine minutes.

At nine minutes and eighteen seconds, Dust’s knees buckled and he dropped to the round, blasters fizzing out of existence in a shower of purple fragments.

Cross stepped up to him as he panted, chest heaving while he barely held himself upright on his hands and knees. He dropped down into a squat and waited for Dust to get his breathing under control.

“You held ten blasters for nine minutes and eighteen seconds. That’s commendable. Good job.”

Dust craned his head up to glare at him, stuck between confusion and that spark he’d had when Nightmare complimented him, too.

“How do you feel?”

Dust scoffed, rolling onto his back and sprawling out right there in the dirt. He groaned, shutting his sockets. “Like shit.”

“And magic-wise?”

“...like _shit,”_ he repeated.

Cross’ teeth quirked up. “Good. From now on, unless Nightmare tells you otherwise, you’ll be coming to me when your magic builds up. Understood?”

There was a pause, and Cross debated whether Dust had passed out or just ignored him. But he cracked an eyesocket open to look at him. The attempt at his usual smirk was laughable at best, but Cross opted not to tell him.

“Does that mean you’ll fuck me, then?”

Cross contemplated his answer. The longer they stared at each other, the more he could see the nervousness setting into the other one, his shoulders hunched, soles digging into the dirt. The crease between his browbones got deeper.

“If you want me to fuck you, it’ll be on my terms,” he said, finally.

Dust replied with a wry laugh, one of his hands twitching where it laid. “Crossy. I can’t fucking move. You can do whatever you want to me.”

“I know.”

Cross shifted until he sat next to Dust and pulled him up against himself. Dust was pliant and let himself be manhandled, almost like a doll. Cross sat him in his own lap, back to chest, and pushed his shorts down.

Dust made a small sound, head lolling back against Cross’ shoulder as he dragged a phalanx over the cloud of lilac magic gathered in his pelvic inlet.

“I’ve got rules for you,” he said, so close to Dust’s acoustic meatus that he could feel the shiver that wracked him. “You will tell me the moment anything hurts. I don’t care if you like it or not, you’ll tell me when you feel any little bit of pain. If you don’t, I will take you to your room and leave.”

Dust groaned, his hips trying to arch into Cross’ touch, but he kept it brief on purpose.

“Dust, did you understand?”

“Ugh… yeah,” Dust muttered.

Cross hummed in thought, and then decided to test it out, pulling the scarlet scarf and hood aside so he could lean down to the column of Dust’s neck. He sunk his teeth into the bone and Dust breathed out in a rush, tensing up.

“Hurts,” he said, though it sounded pleased.

Satisfied, Cross let go and licked out the few drops of marrow that welled on the surface. “Good. Look how good you can be when you want to. The moment you don’t tell me, I’m leaving, though. Keep it in mind.”

“Okay,” Dust slurred. The cloud of magic grew hotter and hotter, and when Cross pulled his hand away, it snapped into place, a little dimmer than earlier that day.

“And tell me the moment you want to stop. Same conditions apply.”

“Okay,” Dust repeated, a little shakier now.

Cross had a nagging feeling he’d say ‘okay’ to just about anything Cross would say right now. Instead of trying, he simply wrapped his hands around his cock, running his phalanges over the length in slow, long drags. It was soaked, the tip all but leaking, and it made the slide smooth and easy.

Cross kept the pace, occasionally rolling his palm over the head and smearing the precum. Dust’s mouth fell slack, sighs and choked moans leaving him in troves. Cross found out he liked it if he dragged a finger right under the head, and even more so when he pushed it against the slit, coaxing out more and more slick.

“W—What’re you doing?” Dust forced out, even as he bucked into the gentle touches. His movements were sluggish, exhaustion clear in him, but Cross just hummed.

“Giving you a handjob, what’s it look like?”

Dust growled, though it came out more like a whine than anything. “Why?”

Cross twisted his wrist on the next downstroke and pulled a lovely moan out of him. The slighter body was downright trembling in his hold, even with a hand on Dust’s thigh to keep him steady.

“What do you mean _why?_ You wanted to be fucked, didn’t you?”

Dust’s hands couldn’t seem to find a place to be, gripping onto Cross’ sleeves one second, his own hoodie the next, fingers twisting in whatever fabric they ended up in. “I— I thought… ah— thought you’d go ahead and fuck me up…”

He was desperately trying to move his hips, but Cross was keeping his touches feather light and pace unhurried. “Aren’t I, though? You didn’t stutter last time.”

Once again, Dust tried to growl at him, and ended up moaning instead. He tried to wiggle out of where Cross was caging him in, without any such luck.

“Fuck… go faster…”

“No point in rushing it,” Cross said, nonchalantly. He twisted his wrist again and Dust let out a keen, turning his head to hide his face in the bulk of Cross’ hood. “Do you want to stop?”

Dust shook his head hard enough to almost headbutt Cross’ chin. “No— No! Don’t fucking stop.”

Cross slid his other hand from Dust’s thigh to his cunt, fingers dragging through the slicked folds. He was soaking wet, and squeezing down on nothing. But Cross didn’t push in, merely kept sliding up and down the length of the slit, dragging softly over the puffy lips.

“Fucking shit—” Dust cursed, simultaneously trying to curl up into himself and arch into the dual sensations, effectively succeeding in neither. “Cross— fuck—”

The guardsman teased at his hole, little circles that never dipped even the tips of his phalanges inside, his other hand rolling the tip of Dust’s cock over his palm.

“I told you to tell me if anything hurts,” Cross chided, pressing into Dust’s slit with a single finger. His hands were coated in the purple slick, loud as they moved.

“Doesn’t— doesn’t hurt—” Dust gasped out. Cross wasn’t sure if he really sounded confused or if he just imagined it.

He pumped his cock in long strokes, tightening his grip just a little when he got to the base. Dust’s shoulders shook and his panting started sounding more and more like sobs.

“You’re allowed to come, Dust,” Cross told him, soothing the crying skeleton with a kiss to his neck, over the shallow bite he’d left earlier. “You listened to me, and did well. You deserve a reward.”

Dust’s back arched, body seizing up. Cross didn’t even feel bad about using underhanded tactics, only stroking Dust through his release as he painted his hand and the ground in stripes of purple. His magic crackled under Cross’ tongue, a taste of static flooding his mouth.

Dust whined, pawing at Cross’ hand when it became too much. Cross took it, considering Dust seemed unable to form actual words at the moment, and pulled away. Dust slumped against him, twitching and gasping for breath. His ribcage was rising and falling so rapidly that Cross almost worried.

“W—What did you do to me?” Dust asked, voice broken like he’d been screaming all day long. He couldn’t seem to get his limbs to listen to him as they just shook uselessly. 

“Don’t tell me you’ve never been jerked off before,” Cross scoffed. He pulled Dust’s shorts up when his ecto-body faded away, though it took a bit of maneuvering.

“That—That wasn’t a handjob!” the other cried. There were tears still streaming down his skull in rivulets, and he gripped Cross’ sleeves with enough force to cut off the leylines in his knuckles. “What the fuck…? What the fuck did you do— to me?”

“You’ll be fine,” Cross assured, sliding a hand under Dust’s knees and hoisting him up. “Just outta magic. Let’s get you into a bed.”

Dust’s sockets were wide as he looked up at Cross, holding onto him for dear life. Though he didn’t protest, didn’t make a single peep, his fear was tangible.

“To sleep,” he amended, fighting a wince. For someone who had bragged about being used when he was unconscious, he didn’t seem to like the idea all that much. Maybe Cross ought to keep watch while he slept. Just in case.

Dust shook against him, obviously still not recovered from his orgasm. Or maybe all the energy he’d discharged at once. Cross wasn’t sure. Maybe it didn’t even matter.

“I’ll bring you to your room,” he said. Dust didn’t reply, didn’t seem to even hear him as Cross teleported them back into the castle.

He wasn’t expecting Nightmare to be in Dust’s room, sitting on the edge of the bed and looking at the mess of clothes strewn about with distaste. His seafoam eyelight flicked up to them, seemingly glowing in the darkness.

“Aside the panic, this is the most content I’ve ever seen him,” Nightmare said, though what he probably meant was ‘feel.’ Cross’ grip on Dust tightened momentarily, before he deposited him onto the bed, tucking him in the wrinkled blanket.

He was already out, even if his fingers kept twitching. Cross turned to face Nightmare, trying his hardest not to appear disrespectful even as he stood his ground.

“It helped him.”

“I don’t doubt it.”

“Aren’t you mad?”

“No,” Nightmare said, simply. His expression was unreadable, and Cross found it unfair that Nightmare knew exactly what he felt. “It’s a good thing. And I’m… glad. It worked better than anything he ever asked for. How did you know what would work?”

Cross swallowed around the sudden dryness of his mouth. “Underfell #327,” he said, “From the Sans there.”

Nightmare hummed, as if he was thinking about something. Cross’ marrow felt like it was freezing as the dark skeleton looked him up and down, like he could see right down to his core, and was picking him apart with nothing but a single eye.

Eventually, he stood up. “Good job. I knew I made the right decision when I brought you in.”

A burst of relief exploded within Cross’s SOUL. He shouldn’t have felt that good about Nightmare’s acknowledgement, but he did nonetheless.

“Keep it up, Cross,” he was told, so he nodded, unable to look away as Nightmare left him in the room with Dust, closing the door with a single tentacle.

That went much better than he’d thought it would, but he still had Killer and Horror to talk to about… well, Dust.

That could wait for later, though. For now, he vowed to make sure the smaller skeleton got some uninterrupted sleep.

**Author's Note:**

> my twitter is @esqers


End file.
